using SHJX.Service.Control.MoveTime.Interface;

namespace SHJX.Service.Control.MoveTime
{
    public class CalculatorContent
    {
        private static readonly ConcurrentDictionary<string, ICalculator> Calculators = new();
        private static CalculatorContent _content;
        private static readonly object locker = new();
        private CalculatorContent() { }
        public static CalculatorContent Instance
        {
            get
            {
                if (_content is null)
                {
                    lock (locker)
                    {
                        _content = new();
                    }
                }
                return _content;
            }
        }

        public ICalculator Factory(string step)
        {
            if (Calculators.TryGetValue(step, out ICalculator value)) return value;
            string className = CreatQueryClassName(step);
            try
            {
                ICalculator calculator = Activator.CreateInstance(Type.GetType(className), true) as ICalculator;
                Calculators.TryAdd(step, calculator);
                return calculator;
            }
            catch
            {
                throw new ArgumentNullException(step);
            }
        }
        private string CreatQueryClassName(string step) => $"{GetType().Namespace}.Handler.{step}Calculator";
    }
}